Cleaning composition for removing sludge from internal-combustion engines



Patented Apr. 15, 1947- CLEANING COMPOSITION FOR REMOVING SLUDGE FROM INTERNAL-COMBUSTION ENGINES George M. Skinner, Kenmore, N. Y., assignor to National Carbon Company, Inc., a corporation of New York No Drawing. Original application April 8, 1942, Serial No. 438,077, new Patent No. 2,403,618, dated July 9, 1946. Divided and this application October 2, 1945, Serial No. 619,903

3 Claims.

The invention relates to the cleaning of metal surfaces, and is particularly concerned with liquid cleaner compositions for removing sludge deposits from the interior parts of internal combustion engines.

/ Under ordinary operating conditions of an internal combustion engine there is usually formed in the crank case, on the surfaces of the combustion chamber, and on other interior working parts; a precipitate or deposit commonly referred to as sludge. This sludge is formed in large part of decomposition products of oil and fuel used in the engine, and may be composed of heavy hydrocarbons, asphaltenes, gums, fine carbon, road dirt and other solid deposits. The sludge accumulates on, and becomes tightly bound to, the piston head and rings, the valve stems and the bearings, and in sufficiently large amounts it may markedly interfere with satisfactory engine operation. The removal of this sludge occasionally is, therefore, desirable, and while efforts have been made to accomplish this by means of various types and kinds of solvent cleaners, the matter of satisfactorily cleaning engines in a quick and easy manner remains a difficult and important problem.

It is an object of this invention to provide improved metal cleaner compositions, adapted more effectively, more readily, and more conveniently to remove sludge deposits from internal combustion engines.

The new cleaner is composed of a plurality of components, in controlled volume proportions to produce a homogeneous liquid mixture of exceptionally'rapid and effective cleaning action. As the essential loosening and dissolving agent for the sludge deposits, one-or more organic solvents are used in an amount comprising at least 50% by volume of the total mixture. Water in an amount from about 5% to 25% of the whole, and oil in quantities preferably not exceeding about 30% by volume are mixed with the solvent, and a coupling agent is then added to produce a stable and homogeneous liquid composition. A detergent may also be included, but by preference the coupling agent selected is one which also will exert a detergent action.

lected from organic ketones, ethers and ester compounds, and the best results have been obtained with mixtures of two or more solvents of different types. The heterogeneous nature of the sludge deposit appears to account for the fact that a single solvent does not usually dissolve or loosen the deposit as Well as a mixture of two or more of them. Glycol monoalkyl ethers are good solvent components, and the cleaning action of these compounds can be further improved by mixing them with liquid aliphatic ketones and aliphatic ester compounds. Especially effective among the latter solvents are di-isobutyl ketone, methyl isobutyl ketone, methyl amyl ketone, mesityl oxide, isophorone and methyl amyl acetate. Where two or more solvents are used, the most suitable proportions of each can be readily determined by test, but the total solvent quantity in the cleaner should preferably be from about 50% to by volume.

Water in the cleaner formula substantially aids in loosening tightly bound sludge, and causes flaking off of lacquer-type deposits, which might not otherwise be attacked by the solvent. At least 5% water is necessary to improve the cleaner performance, and it preferably should not exceed 25% by volume. The purpose of an oil addition is to afford lubricating properties, and prevent rusting of the metal surfaces after cleaning. Ordinary mineral lubricating oils are satisfactory for this use, and the oil proportions preferably vary from about 15% to 25% by volume.

A coupling agent is necessary to render the oilwater-solvent mixture homogeneous, and thereby insure proper functioning of the cleaner both as initially formulated and after storage in containers. Some of the solvents above mentioned may in themselves assist in coupling of the completed mixture, but a, further additive specifically for this purpose is usually desirable. Many compounds are available which may be suitable in their homogenizing effect, among which amine soaps are preferred, since these compounds also have certain detergent action, and thus further improve the solvent efliciency. Morpholine soaps, such as morpholine oleate and morpholine ricinoleate have proven especially elfective as coupling and detergency agents. Certain free amines, in addition to the amine soap, may also'be added, if desired, and compounds like morpholine, octyl Percent by volume Mineral lubricating oil S. A. E. 20 18 Water 5 Ethylene glycol monoethyl ether 15 Mesityl oxide 22 Methyl amyl acetate 30 Morpholine oleate I In th manner of use and application of these cleaner compositions, no restrictions are intended by the present disclosure, but a distinct advantage lies in the ease and convenience with which satisiactory cleaning can be eflected. With an engine still in running order, a cleaning treatment may consist in slowly adding a pint or so of the sludge remover through the carburetor air intake while operating at a speed just sufiicient to prevent stalling. In this process the cleaner is carried directly into the combustion chambers and is later expelled through the exhaust manifold. Thus, the valves, pistons, piston rings and combustion chambers are exposed to the cleaner, and the very small quantities of the cleaner which may pass the piston rings into the crank case, are not sufficient to cause any deleterious action on, or dilution of, the crank case oil.

Where the sludgin is very severe and the most effective cleaning action is desired, the treatment above can be augmented by crank case cleaning. This is accomplished by draining the crank case and refilling it to normal level with the concentrated cleaner formula before starting addition of cleaner to the carburetor. At th conclusion of the carburetor treatment, the crank case is again drained, and may be flushed with light oil. This combination treatment effects excellent cleaning of the crank case, inner engine surfaces, bearings and oil passages, as well as all parts of the combustion chambers. In case of complete engine seizure by heavy sludge, introduction of the cleaner into the spark plug holes, followed by a period of soaking, is usually efiective in loosening the deposits. Where overhauling or dismantling of the engine is necessary, the cleaner compostion can, of course, be used in the ordinary way, and will be found rapidly effective in cleaning all metal surfaces.

In the particular liquid mixture proposed, consideration has also been given to factors such as toxicity and odor, flash point, corrosiveness, and attack on gasket materials. These formulae are satisfactory in such respects, having no odor that is obnoxious, and being entirely safe to handle 4 under the ordinary precautions used in handling common solvents. They are not irritating to the .skin, and they do not readily corrode metals or' attack gasket material.

It will be understood, however, that the specific cleaner formula given is merely representative, and that numerous modifications in the various components, and their proportions, may be made with the advantages described. Such modifications are intended to be included within the broader scope of the invention. This application is a division of my copending application Serial No. 438,077, filed April 8, 1942 issued as Patent No. 2,403,618 on July 9, 1946.

I claim:

1. A cleaning composition for removing sludge from internal combustion engines consisting of a homogeneous liquid mixture of a solvent composed of a glycol monoalkyl ether, a higher molecular weight aliphatic ketone, and methyl amyl acetate, each in appreciable component proportions and in total amount of about 50% to by volume; a lubricating oil in an amount from about 15% to 25%; about 5% to 25% of water; and about 5% to 20% of a morpholine soap coupling agent,

2. A cleaning composition for removing sludge from internal combustion engines consisting of a homogeneous liquid mixture of a solvent composed of ethylene glycol monoethyl ether, mesityl oxide, and methyl amyl acetate, each in appreciable component proportions and in total amount of at least 50% by volume; a mineral lubricating oil in an amount not exceeding 30%; at least 5% of water; and about 5% to 20% of a morpholine soap coupling agent.

3. A cleaning composition for removing sludge from internal combustion engines comprising a homogeneous liquid mixture, in proportions by volume, of about 15% ethylene glycol monoethyl ether, about 22% mesityl oxide, about 30% methyl amyl acetate, about 18% mineral oil, about 5% water, and about 10% morpholine oleate.

GEORGE M. SKINNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,128,685 Yates Aug. 30, 1938 2,259,872 Baldeschwieler et al. Oct. 21, 1941 2,032,174 Johnson Feb, 25, 1936 1,822,886 Elderkin Sept. 15,1931 1,787,789 Lovell et a1 Jan. 6, 1931 1,833,429 Lovell et al. -Nov. 24, 1931 OTHER REFERENCES Ind. and Eng. Chem, vol. 27, No. 8 (Aug. 1935), pages 867-871, article by A. L. Wilson, entitled New Aliphatic Amines. a 

